Microsoft® JScript®
! Operator
 Language Reference 
Version 1 

See Also

Performs logical negation on an expression.
result = !expression

The ! operator syntax has these parts:

Part Description
result Any variable.
expression Any expression.

The following table illustrates how result is determined.

If expression is Then result is
True False
False True

All unary operators, such as the ! operator, evaluate expressions as follows:

The operator is applied to the resulting number.

For the ! operator, if expression is nonzero, result is zero. If expression is zero, result is 1.